Digital repeater having bandpass filtering, adaptive pre-equalization and suppressin of natural oscillation

Patent metadata

Field	Value
Publication number	US-9929793-B2
Application number	US-201514952364-A
Country	US
Kind code	B2
Filing date	Nov 25, 2015
Priority date	Nov 12, 2001
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

A signal repeating system includes at least one input antenna that receives input signals, at least one output antenna that radiates output signals, and a signal path between the input and output antennas. The signal path includes circuitry for conditioning the input signals with down conversion circuitry that converts input signals to lower frequency signals and analog-to-digital conversion circuitry that converts the input signals to digital signals. A suppression circuit suppresses feedback and interference in the repeated output signals with a digital signal processor configured for receiving samples of the input signals, samples of the output signals, and samples of an interference reference signal and an adaptive filter under the control of the digital signal processor for generating echo cancellation signals and interference cancellation signals.

First claim

What is claimed is:

1. A unit for repeating an input analog downstream radio frequency signal output by a base station, the unit comprising:
a digital signal processor to digitally process first downstream digital samples derived from the input analog downstream radio frequency signal in order to generate output downstream digital samples, wherein the unit is located remotely from the base station;
a digital-to-analog converter; and
a power amplifier;
wherein the unit is configured to generate an amplified analog downstream radio frequency signal from the output downstream digital samples using, at least in part, the digital-to-analog converter and the power amplifier;
wherein the unit is configured to radiate an output analog downstream radio frequency signal from an antenna associated with the unit, wherein the antenna is located remotely from the base station and wherein the output analog downstream radio frequency signal is derived from the amplified analog downstream radio frequency signal;
wherein the output analog downstream radio frequency signal comprises a repeated version of the input analog downstream radio frequency signal;
wherein the unit further comprises:
an upstream signal path comprising a first analog-to-digital converter, wherein the upstream signal path is configured to generate upstream digital samples derived from an input analog upstream radio frequency signal using, at least in part, the first analog-to-digital converter; and
a feedback signal path comprising a second analog-to-digital converter, wherein the feedback signal path is configured to generate feedback digital samples derived from the amplified analog downstream radio frequency signal, wherein at least a portion of the feedback digital samples are input to the digital signal processor; and

wherein the digital signal processor is configured to perform digital distortion correction for the output downstream digital samples using the at least the portion of the feedback digital samples input to the digital signal processor.

2. The unit of claim 1 , wherein the digital signal processor is configured to perform digital adaptive distortion correction for the output downstream digital samples using the at least the portion of the feedback digital samples.

3. The unit of claim 1 , wherein the first downstream digital samples comprise first downstream digital in-phase (I) and quadrature (Q) samples.

4. The unit of claim 1 , wherein the first downstream digital samples comprise first downstream digital quadrature-modulated samples.

5. The unit of claim 1 , wherein the first downstream digital samples comprise first downstream digital baseband samples.

6. The unit of claim 1 , wherein the unit is configured to receive the input analog upstream radio frequency signal; and
wherein the upstream digital samples are for use in generating an output analog upstream radio frequency signal that is output to the base station.

7. The unit of claim 1 , further comprising a mixer, wherein the unit is configured to generate the amplified analog downstream radio frequency signal from the output downstream digital samples using, at least in part, the digital-to-analog converter, the mixer, and the power amplifier.

8. The unit of claim 1 , wherein the digital signal processor is configured to perform the digital distortion correction for the output downstream digital samples corresponding to at least one selected frequency band of the input analog downstream radio frequency signal.

9. The unit of claim 1 , wherein the digital signal processor is configured to perform the digital distortion correction for the output downstream digital samples corresponding to at least one selected channel of the input analog downstream radio frequency signal.

10. The unit of claim 1 , wherein the input analog downstream radio frequency signal comprises a frequency band for providing a wireless service, wherein the digital signal processor is configured to perform the digital distortion correction for the output downstream digital samples corresponding to at least one selected sub-band of the input analog downstream radio frequency signal.

11. The unit of claim 10 , wherein each of the at least one selected sub-band of the input analog downstream radio frequency signal comprises a respective selected channel within the frequency band for providing the wireless service.

12. A unit for repeating an input analog downstream radio frequency signal output by a base station, the unit comprising:
a circuit to digitally process first downstream digital samples derived from the input analog downstream radio frequency signal in order to generate output downstream digital samples, wherein the unit is located remotely from the base station;
a digital-to-analog converter; and
a power amplifier;
wherein the unit is configured to generate an amplified analog downstream radio frequency signal from the output downstream digital samples using, at least in part, the digital-to-analog converter and the power amplifier;
wherein the unit is configured to radiate an output analog downstream radio frequency signal from an antenna associated with the unit, wherein the antenna is located remotely from the base station and wherein the output analog downstream radio frequency signal is derived from the amplified analog downstream radio frequency signal;
wherein the output analog downstream radio frequency signal comprises a repeated version of the input analog downstream radio frequency signal;
wherein the unit further comprises:
an upstream signal path comprising a first analog-to-digital converter, wherein the upstream signal path is configured to generate upstream digital samples derived from an input analog upstream radio frequency signal using, at least in part, the first analog-to-digital converter; and
a feedback signal path comprising a second analog-to-digital converter, wherein the feedback signal path is configured to generate feedback digital samples derived from the amplified analog downstream radio frequency signal using, at least in part, the second analog-to-digital converter, wherein at least a portion of the feedback digital samples are input to the circuit and

wherein the circuit is configured to perform digital distortion correction for the output downstream digital samples using the at least the portion of the feedback digital samples that are input to the circuit.

13. The unit of claim 12 , wherein the circuit comprises a digital signal processor.

14. The unit of claim 12 , wherein the circuit is configured to perform adaptive digital distortion correction for the output downstream digital samples using the at least the portion of the feedback digital samples.

15. The unit of claim 12 , wherein the feedback signal path includes:
a mixer to down-convert the amplified analog downstream radio frequency signal; and
wherein the second analog-to-digital converter generates the feedback digital samples from the down-converted amplified analog downstream radio frequency signal.

16. The unit of claim 12 , wherein the unit is configured to receive the input analog upstream radio frequency signal; and
wherein the upstream digital samples are for use in generating an output analog upstream radio frequency signal that is output to the base station.

17. A method of repeating an input analog downstream radio frequency signal output by a base station, the method comprising:
digitally processing, at a unit, first downstream digital samples derived from the input analog downstream radio frequency signal output by the base station in ord

Assignees

• Andrew Wireless Systems Gmbh

Inventors

• Kummetz Thomas

Classifications

• H04B7/15585 Primary

  by interference cancellation · CPC title